I couldn't tell the difference between the p3a and a cheap dvd player
You are very lucky!
I wish I couldn´t hear difference between components so that I could spend my money and time on more worthwhile pursuits.
So.. what to do?
Get a vinyl record player!
I think the p3a is pretty good value and modded even better.Have you changed caps?
Kidding aside I find it surprising that you cannot hear any difference.I hear differences between opamps much less other players.Maybe they need some break-in like everything else?
I don´t know what your diy skills are but in my view it is worth selling your dac on ebay and picking up a good non-os dac kit for half what you are going to get.
You are very lucky!
I wish I couldn´t hear difference between components so that I could spend my money and time on more worthwhile pursuits.
So.. what to do?
Get a vinyl record player!
I think the p3a is pretty good value and modded even better.Have you changed caps?
Kidding aside I find it surprising that you cannot hear any difference.I hear differences between opamps much less other players.Maybe they need some break-in like everything else?
I don´t know what your diy skills are but in my view it is worth selling your dac on ebay and picking up a good non-os dac kit for half what you are going to get.
P Stack Mods
Greetings, I am having trouble determining what mods to get for my P-Stack setup.
Here is the plan:
P3a DAC:
1. Upgrade OPAMPs to 627AP from Futurlec
2. Change diodes (4x) in rectifier bridge to 8A 600V TO-200 Fairchild soft recovery FREDs $2.95 ea from percey audio
3. Upgrade power supply and signal path electrolyics. I am not sure about htis one as the capacitors appear to be good quality. The 220, 100, and 47uF appear doable, but is it necessary?
P1a:
1. Upgrade diodes and power supply caps as above
P3b:
1. Upgrade 10000uF 16V co-brand capacitor to Nichicon 10000uF, 50V SuperThrough KG cap. I see that it is 100mm long, so I will have to lay it on its side. (Is this OK?)
2. Upgrade the filter Cap. I cannot be sure what value/tye to use as this one is labled with the number 100 over 47uF. It looks like a chip capacitor, but I am not sure what to replace it with....HELP!
3. Resistor. Can someone look at the resistor and tell me its value? I am color-blind and cannot read the banding codes.
I intend to use a caddock MK-132 in its place.
4. Replace the diodes with 4 15A 600V TO-200 fairchilds.
"Please Help Me Obi-Wan, you're my only hope..."
Greetings, I am having trouble determining what mods to get for my P-Stack setup.
Here is the plan:
P3a DAC:
1. Upgrade OPAMPs to 627AP from Futurlec
2. Change diodes (4x) in rectifier bridge to 8A 600V TO-200 Fairchild soft recovery FREDs $2.95 ea from percey audio
3. Upgrade power supply and signal path electrolyics. I am not sure about htis one as the capacitors appear to be good quality. The 220, 100, and 47uF appear doable, but is it necessary?
P1a:
1. Upgrade diodes and power supply caps as above
P3b:
1. Upgrade 10000uF 16V co-brand capacitor to Nichicon 10000uF, 50V SuperThrough KG cap. I see that it is 100mm long, so I will have to lay it on its side. (Is this OK?)
2. Upgrade the filter Cap. I cannot be sure what value/tye to use as this one is labled with the number 100 over 47uF. It looks like a chip capacitor, but I am not sure what to replace it with....HELP!
3. Resistor. Can someone look at the resistor and tell me its value? I am color-blind and cannot read the banding codes.
I intend to use a caddock MK-132 in its place.4. Replace the diodes with 4 15A 600V TO-200 fairchilds.
"Please Help Me Obi-Wan, you're my only hope..."
No Offense
I have the full mouser catalogue at home...lov'n it. Sadly, I am still colorblind and unable to figure out what kind of cap I should use for C2 in the power supply (Monolithic Perpetual PS)
With Audiocircle, I don't get it...
I've never been a member, never posted...but I am banned!?
...I showered, I swear...
I have the full mouser catalogue at home...lov'n it. Sadly, I am still colorblind and unable to figure out what kind of cap I should use for C2 in the power supply (Monolithic Perpetual PS)
With Audiocircle, I don't get it...
I've never been a member, never posted...but I am banned!?
...I showered, I swear...
OK....now you have me confused........not nice to confuse us old farts.......
"Upgrade the filter Cap. I cannot be sure what value/tye to use as this one is labled with the number 100 over 47uF. It looks like a chip capacitor......."
Well, if it is a chip cap, then it is not a filter cap. Right? And would most likely not have any markings on it.
So which is it???
Anyway....you have a Mouser catalog....get one from Digi-key, too. Especially if you want Burr-Brown parts. Panasonic caps. Etc.
Jocko
"Upgrade the filter Cap. I cannot be sure what value/tye to use as this one is labled with the number 100 over 47uF. It looks like a chip capacitor......."
Well, if it is a chip cap, then it is not a filter cap. Right? And would most likely not have any markings on it.
So which is it???
Anyway....you have a Mouser catalog....get one from Digi-key, too. Especially if you want Burr-Brown parts. Panasonic caps. Etc.
Jocko
We young'ns gotta learn...
Well, I figured out the problem with AudioCircle: no Yahoo accounts allowed...easy fix.
1. The 100 47uF capacitor is in line with the 10000uF 16V Electrolytic cap on the power supply circuit board. I do not recognize the capacitor type, but is appears to be a small, 8x7 mm, metallic box. The face of the box has the number "100" printed above "47uF" I am taking it to mean that it is a 100V, 16V cap. I really don't know what to call it, but the boxy shape seemed similar to the MLC chip capacitors in my Mouser Catalog.
2. The Resistor is another fun one. I can't tell the colors on the bands, but it is a five band marker. I will just test it with my multi-meter... Help would be appreciated if anyone happens to know...it also connects to the small red LED light at the front of the chassis.
3. The P3a DAC and P1a will be equally fun, but I think I need to focus on the PS for now.
Well, I figured out the problem with AudioCircle: no Yahoo accounts allowed...easy fix.
1. The 100 47uF capacitor is in line with the 10000uF 16V Electrolytic cap on the power supply circuit board. I do not recognize the capacitor type, but is appears to be a small, 8x7 mm, metallic box. The face of the box has the number "100" printed above "47uF" I am taking it to mean that it is a 100V, 16V cap. I really don't know what to call it, but the boxy shape seemed similar to the MLC chip capacitors in my Mouser Catalog.
2. The Resistor is another fun one. I can't tell the colors on the bands, but it is a five band marker. I will just test it with my multi-meter... Help would be appreciated if anyone happens to know...it also connects to the small red LED light at the front of the chassis.
3. The P3a DAC and P1a will be equally fun, but I think I need to focus on the PS for now.
Re: Perpetual P-3a and Opamp Class A Bias
Hello David,
I'm not sure the correct way to measure the dynamic impedance of the ccs is using a static measurement method. By raising the DC voltage accross the ccs, you also introduce thermal issues, different dissipation of the ccs. I would suggest modulating the voltage accross the ccs, and measuring the voltage drop accross a small series resistor with a scope.
NET Audio said:
Hello David,
I'm not sure the correct way to measure the dynamic impedance of the ccs is using a static measurement method. By raising the DC voltage accross the ccs, you also introduce thermal issues, different dissipation of the ccs. I would suggest modulating the voltage accross the ccs, and measuring the voltage drop accross a small series resistor with a scope.
I know I am raising this thread from the dead but I have a lightly-used set of the P-1A and P-3A in boxes in my closet but the power warts for them have been misplaced. Among all the discussion on this thread, I gather that the stock PS is 9VAC. Is that true and true for both of them? I would like to resuscitate them and dispose of them. ;-)
Kal
Kal
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